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Pei Lin

Publications and source records attributed to Pei Lin.

At least 37 records · Page 2Linked to original sources
PubMed2005

Acute myeloid leukaemia with FLT3 gene mutations of both internal tandem duplication and point mutation type.

FLT3 gene mutations, either internal tandem duplication or point mutation type, are common in acute myeloid leukaemia (AML). We describe 21 AML cases with both types of gene mutations, so-called dual mutations, representing approximately 1% of all cases. Most newly diagnosed AML with FLT3 dual mutations had monocytic differentiation and a normal karyotype. Over the disease course, changes in FLT3 mutation status were seen in 89% of cases, and were associated with cytogenetic changes. We conclude that FLT3 dual mutations occur rarely in AML, and appear to be related to clonal evolution.

Acute Disease↗
PubMed2005

Immunophenotypic profile of lymphoplasmacytic lymphoma/Waldenström macroglobulinemia.

We retrospectively reviewed the immunophenotypic profile of 75 cases of lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM) analyzed by flow cytometry. All patients had monoclonal IgM (median, 2,100 mg/dL [21 g/L]) in serum and were considered clinically to have WM. The neoplastic cells, in all cases, expressed monoclonal immunoglobulin light chain (k, 55; l, 20) and CD19, and every case assessed was positive for CD20 (n=68) and CD52 (n=60). The results for other antigens assessed in decreasing frequency of positivity were as follows: surface IgM (26/28 [93%]), CD79b (11/13 [85%]), CD11c (13/16 [81%]), CD25 (5/7 [71%]), CD23 (17/28 [61%]), CD38 (24/50 [48%]), FMC7 (11/29 [38%]), CD22 (4/12 [33%]), CD5 (3/65 [5%]), and CD10 (1/38 [3%]). These results show that the immunophenotype of LPL/WM is variable and overlaps with other B-cell lymphoproliferative disorders. CD23, usually of dim intensity, and CD11c are expressed commonly in LPL/WM. Rare CD5+ and CD10+ cases of LPL/WM also exist.

Adult↗
PubMed2005

inv(16)(p13q22) in chronic myelogenous leukemia in blast phase: a clinicopathologic, cytogenetic, and molecular study of five cases.

Blast phase (BP) in chronic myelogenous leukemia (CML) frequently is accompanied by cytogenetic abnormalities in addition to t(9;22)(q34;q11.2). We describe 5 patients with CML in blast phase (CML-BP) in which t(9;22) and inv(16)(p13q22) were identified by conventional cytogenetics, with confirmation of BCR-ABL and CBFss-MYH11 by fluorescence in situ hybridization. The morphologic findings at the time of BP resembled de novo acute myeloid leukemia (AML) carrying inv(16)(p13q22), with abnormal eosinophils in the bone marrow and monocytosis in the peripheral blood in all cases. In 1 patient, inv(16)(p13q22) and abnormal eosinophils were detected in the bone marrow 2 months before CML-BP. The clinical course of these patients was similar to patients with CML-BP without evidence of inv(16)(p13q22). These cases illustrate that inv(16)(p13q22) is a form of cytogenetic evolution that rarely occurs in patients with CML at the time of BP. In this setting, unlike de novo AML, inv(16)(p13q22) in CML-BP is not associated with a favorable prognosis.

Adult↗
PubMed2005

Chronic lymphocytic leukemia/small lymphocytic lymphoma associated with IgM paraprotein.

We studied the clinicopathologic, immunophenotypic, and cytogenetic features of 26 patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) associated with serum IgM paraprotein. The study group (16 men; 10 women; median age, 64 years; range, 40-82 years) represents approximately 2.5% of CLL/SLL cases at our institution. The paraprotein level ranged from 1 to 14 g/L (median, 4 g/L). Neoplasms in bone marrow were composed of small round lymphocytes arranged in nodular (n = 6), diffuse (n = 5), interstitial (n = 5), or mixed (n = 10) patterns. All cases were positive for monotypic surface immunoglobulin light chain, IgM/IgD, CD5, CD19, CD20, and CD23. CD11c (14/20 [70%]), CD79b (11/19 [58%]), FMC-7 (11/26 [42%]), CD22 (8/20 [40%]), and ZAP-70 (6/19 [32%]) were expressed in subsets of cases. Of 17 bone marrow specimens assessed by conventional cytogenetics, 6 were abnormal and 11 were diploid. The overall survival of this group (median follow-up, 24 months) was not significantly different from that for an age-, sex-and stage-matched group of 52 CLL/SLL patients without IgM paraprotein (P = .60). We conclude that CLL/SLL cases with serum IgM paraprotein are similar to other CLL/SLL cases in their clinicopathologic and immunophenotypic features.

Adult↗
PubMed2005

Postsplenectomy cytomegaloviral mononucleosis: marked lymphocytosis, TCRgamma gene rearrangements, and impaired IgM response.

People who have undergone splenectomy mount a poor IgM response to bacterial polysaccharide vaccines. Whether this defect is true during natural bacterial and viral infections is unknown. We present 2 cases of postsplenectomy cytomegalovirus (CMV)-induced mononucleosis with impaired IgM but normal to augmented IgG response. The cases presented initial diagnostic challenges owing to a prolonged course of infection, marked lymphocytosis (peak lymphocyte count, 27,900/microL [27.9 10(9)/L]), clonal T-cell proliferation with T-cell receptor g gene rearrangements, and remote history of splenectomy. However, the acute nature of the infections, serial determinations of the anti-CMV IgM and IgG, exclusion of other causes, and detection of CMV in the blood established the diagnosis and revealed the deranged antibody response. The infections resolved without specific treatment. These cases suggest that the spleen might be a primary site for specific anti-CMV IgM response.

Adult↗
PubMed2005

Myeloid sarcoma involving the testis.

Myeloid sarcoma is a neoplasm of immature granulocytes, monocytes, or both involving any extramedullary site. Myeloid sarcoma involving the testis, however, is uncommon and very rarely occurs as an isolated mass. We describe 4 patients with myeloid sarcoma involving the testis, including 2 patients in whom the neoplasm was isolated to the testis (1 unilateral and 1 bilateral). Histologically, 4 neoplasms were poorly differentiated and 1 was blastic. Each neoplasm was shown to be of myeloid lineage, and negative for T- and B-cell specific antigens using immunohistochemical methods. One case was also positive for chloroacetate esterase. In the literature, most cases of myeloid sarcoma involving the testis represent relapse or the initial presentation of acute myeloid leukemia. Including the 2 cases we report here, only 7 cases of myeloid sarcoma isolated to the testis have been reported.

Adult↗
PubMed2005

Morphologic, cytogenetic, and molecular abnormalities in therapy-related acute promyelocytic leukemia.

We describe 17 cases of therapy-related acute promyelocytic leukemia (tAPL). Treatment for the initial neoplasms (mostly carcinomas and non-Hodgkin lymphomas) included radiation and chemotherapy in 11 patients, radiation in 3, and chemotherapy in 3. The interval between the initial neoplasm and tAPL ranged from 17 to 166 months (median, 40 months). Morphologically, all 13 cases with available bone marrow aspirate smears showed tAPL. Dyserythropoiesis or dysmegakaryopoiesis was identified in 11 cases. In 2 cases, too few nonneoplastic cells and, in all cases, too few maturing granulocytes were present to assess for dysplasia. Conventional cytogenetics or fluorescence in situ hybridization (FISH) showed the t(15;17)(q22;q21) in all cases; 6 as a sole abnormality, 9 with additional abnormalities, and 2 assessed only by FISH. Reverse transcription-polymerase chain reaction (PCR) studies showed PML/RARa in 13 cases (8 short form, 5 long form). Mutations of the flt3 gene were detected by PCR in 5 (42%) of 12 cases. We conclude that dysplastic features, secondary cytogenetic abnormalities, and flt3 mutations are common in tAPL.

Adult↗
PubMed2005

Lymphoid neoplasms associated with IgM paraprotein: a study of 382 patients.

We identified 382 consecutive patients with lymphoid neoplasms associated with serum monoclonal IgM paraprotein and classified each neoplasm according to World Health Organization criteria. Lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM) was most common, 225 cases (median serum IgM level, 2.2 g/dL; range, 0.2-10.9 g/dL). For 157 cases, classification and median (and range in g/dL) IgM levels were as follows: chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL; n = 77), 0.9 (0.1-2.1); marginal zone lymphoma (n = 27), 0.5 (0.1-2.4); follicular lymphoma (n = 18), 0.4 (0.1-1.6); mantle cell lymphoma (n = 11), 0.4 (0.2-1.3); diffuse large B-cell lymphoma (DLBCL; n = 7), 0.5 (0.2-1.0); DLBCL associated with low-grade lymphoma (n = 5), 0.9 (0.4-3.0); angioimmunoblastic T-cell lymphoma (n = 4), 0.8 (0.8); and CD5+CD23- low-grade B-cell lymphoma, unclassified (n = 8), 0.5 (0.3-2.9). The results show IgM paraproteinemia was associated most commonly with LPL/WM (58.9%), followed by CLL/SLL (20.2%). Although serum IgM levels greater than 3 g/dL were restricted to patients with LPL/WM, most patients with LPL/WM had paraprotein levels less than 3 g/dL. Thus, serum IgM paraprotein level is not a reliable discriminator in differential diagnosis.

Female↗
PubMed2004

Expression of PAX5 in CD20-positive multiple myeloma assessed by immunohistochemistry and oligonucleotide microarray.

Silencing of PAX5 gene by upregulation of B-lymphocyte-induced maturation protein-1 (PRDM1) is essential for terminal differentiation of B cells to plasma cells. To investigate PAX5 gene expression and its protein product, B-cell-specific activator protein (BSAP), in a subgroup of multiple myeloma characterized by CD20 expression, we studied PAX5/BSAP by immunohistochemistry in 25 cases of myeloma, all expressing moderate to strong CD20 by flow cytometric analysis, and correlated the results with PAX5 and PRDM1 mRNA levels analyzed by the Affymetrix HuGeneFL GeneChip microarray in 17 cases. Using paraffin-embedded bone marrow biopsy sections, we found PAX5/BSAP was expressed in 72% (18/25) of cases overall with an intensity ranging from weak (10, 56%) to strong (8, 44%). PAX5/BSAP was negative in 10 randomly selected CD20-negative myelomas included as negative controls. PAX5 mRNA levels correlated inversely with that of PRDM1 in both CD20-positive and CD20-negative myelomas and failed to predict the expression levels of PAX5/BSAP, suggesting that detected PAX5/BSAP likely represents remnant of earlier stage of development. We conclude that CD20-positive myelomas expressing PAX5/BSAP can present as a diagnostic pitfall mimicking B-cell neoplasms with plasmacytoid differentiation.

Adult↗
PubMed2004

Acute myeloid leukemia with t(6;9)(p23;q34) is associated with dysplasia and a high frequency of flt3 gene mutations.

We report 12 cases of t(6;9)(p23;q34)-positive acute myeloid leukemia (AML), all classified using the criteria of the World Health Organization classification. There were 10 women and 2 men with a median age of 51 years (range, 20-76 years). Dysplasia was present in all cases (9 previously untreated), and basophilia was present in 6 (50%). Immunophenotypic studies showed that the blasts were positive for CD9, CD13, CD33, CD38, CD117, and HLA-DR in all cases assessed. CD34 was positive in 11 (92%) of 12, and terminal deoxynucleotidyl transferase was positive in 7 (64%) of 11 cases. The t(6;9) was the only cytogenetic abnormality detected in 7 cases (58%), and 5 cases had additional chromosomal abnormalities. Of 8 cases assessed, 7 (88%) had flt3 gene mutations. We conclude that t(6;9)-positive AML cases have distinctive morphologic features, an immunophenotype suggesting origin from an early hematopoietic progenitor cell, and a high frequency of flt3 gene mutations.

Acute Disease↗
PubMed2004

Flow cytometric immunophenotypic analysis of 306 cases of multiple myeloma.

Bone marrow aspirates from 306 patients with multiple myeloma were analyzed by flow cytometric immunophenotyping. The plasma cells (PCs) were identified by their characteristic light scatter distribution and reactivity patterns to CD138, CD38, and CD45. Monoclonality was confirmed by immunoglobulin light chain analysis. The immunophenotypic profile of the PCs was determined with a panel of antibodies. Moderate to bright expression of CD56, CD117, CD20, CD45, and CD52 was detected in 71.7%, 17.8%, 9.3%, 8.8%, and 5.2% of cases, respectively. These antigens were expressed by a distinct subpopulation of the PCs in 6.3%, 2.2%, 3.7%, 2.9%, and 2.6% of additional cases. CD19 was negative in more than 99% of cases. The combination of CD38 and CD138 was superior to CD38 alone for identifying CD45+ myeloma and separating CD20+ myeloma from B-cell lymphoma. PC immunophenotyping might be useful for detecting minimal residual disease in cases with aberrant antigen expression and for selection of therapeutic agents that have specific membrane targets.

Adult↗
PubMed2004

t(8;21)(q22;q22) in blast phase of chronic myelogenous leukemia.

The blast phase of chronic myelogenous leukemia (CML) frequently is associated with cytogenetic evidence of clonal evolution, defined as chromosomal aberrations in addition to the t(9;22)(q34;q11.2). We identified the t(8;21)(q22;q22) and other cytogenetic abnormalities by conventional cytogenetics and fluorescence in situ hybridization in 2 patients with t(9;22)-positive CML at the time of blast phase. The t(8;21), which typically is associated with a distinct subtype of de novo acute myeloid leukemia (AML) carrying the aml1/eto fusion gene, was accompanied by increased bone marrow myeloblasts (33%) in case 1 and extramedullary myeloid sarcoma in case 2, suggesting its possible role in disease progression. In case 1, the leukemic cells in aspirate smears had salmon-colored cytoplasmic granules, and immunophenotypic studies showed that the blasts expressed CD19. These findings suggest that the pathologic features of blast phase CML with the t(8;21) resemble those of de novo AML with the t(8;21).

Blast Crisis↗
PubMed2004

Expression of CD2 in acute promyelocytic leukemia correlates with short form of PML-RARalpha transcripts and poorer prognosis.

We studied the immunophenotype of 100 cases of acute promyelocytic leukemia (APL) with cytogenetic evidence of t(15;17)(q22;q21), 72 hypergranular (M3) and 28 microgranular (M3v), and correlated the results with molecular and clinical features. Most neoplasms (75/100 [75%]) had a typical immunophenotype: CD13+CD33+CD34-HLA-DR-. CD64, CD2, CD34, and HLA-DR were expressed in 27% (24/88), 23% (22/94), 21% (21/100), and 9% (9/98), respectively. CD34 expression was restricted to M3v; HLA-DR and CD2 were expressed more often in M3v than in M3 (P < .001). PML-RARalpha fusion transcripts were detected by reverse transcriptase-polymerase chain reaction in all 70 patients assessed. The short form of PML-RARalpha transcripts was found more frequently in M3v (P < .002) and CD2+ APL (P < .0001) than in M3 and CD2- APL, respectively. The median follow-up was 128 weeks. CD2+ APL was associated significantly with leukocytosis (P = .004), shorter complete remission duration (P = .03), and a trend toward shorter overall survival (P = .07) than CD2- APL. Overall survival for M3v vs M3 (P = .68) and short vs long transcripts (P = .21) was not significantly different. Immunophenotyping is useful for predicting the biologic and clinical behavior of APL.

Adolescent↗
PubMed2003

The distinct gene expression profiles of chronic lymphocytic leukemia and multiple myeloma suggest different anti-apoptotic mechanisms but predict only some differences in phenotype.

We compared gene expression in purified tumor cells from untreated patients with chronic lymphocytic (CLL) (n=24) and newly diagnosed multiple myeloma (MM) (n=29) using the Affymetrix HuGeneFL microarray with probes for approximately 6800 genes. Hierarchical clustering analysis showed that CLL and MM have distinct expression profiles (class prediction). Gene and protein expression (measured by flow cytometry) correlated well for CD19, CD20, CD23, and CD138 in CLL and MM, but not for immunoglobulin light chain, CD38 and CD79b in CLL, or CD45 and CD52 in MM. CLL and MM differentially expressed 18% of 130 apoptosis related genes, suggesting differences in mechanisms of cell survival.

Antigens, CD↗
PubMed2003

Mobilization of CD34+ cells in elderly patients (>/= 70 years) with multiple myeloma: influence of age, prior therapy, platelet count and mobilization regimen.

The mobilization of peripheral blood stem cells was studied in 984 multiple myeloma patients, including 106 patients aged >/= 70 years. Increasing age correlated inversely with CD34+ yield (P < 0.0001), but also with >/= 12 months of prior standard chemotherapy (P = 0.0001), < 200 x 10(9)/l platelets (P = 0.0006) premobilization and mobilization with growth factors only (P = 0.0001). After controlling for these age covariates, multivariate analysis identified </= 12 months standard therapy and platelet count >/= 200 x 10(9)/l premobilization as favourable variables (both P < 0.0001), while increasing patient age remained an unfavourable factor (P = 0.0009). With both favourable variables, 85% of elderly patients collected >/= 4 x 10(6)/kg CD34+ cells in a median of one collection. The effect of age was incremental with no age threshold showing acceleration in the decline of CD34+ yield. Chemotherapy significantly increased CD34+ yield compared with growth factors only. However, the subgroup of patients with > 12 months prior therapy and premobilization platelet count < 200 x 10(9)/l mobilized as many CD34+ cells with granulocyte colony-stimulating factor (G-CSF) alone as with chemotherapy and haematopoietic growth factors. Increasing patient age had no effect on post-transplant neutrophil recovery, but significantly delayed platelet recovery (>/= 50 x 10(9)/l) if < 2 x 10(6)/kg CD34+ cells were infused, but this effect was eliminated completely with infusion of >/= 4 x 10(6)/kg CD34+ cells. Increasing age adversely affected CD34+ yield even with limited premobilization therapy, indicating that early collection is important in elderly patients.

Adult↗
PubMed2003

Waldenstrom macroglobulinemia involving extramedullary sites: morphologic and immunophenotypic findings in 44 patients.

Waldenstrom macroglobulinemia (WM) is a clinicopathologic syndrome in which a B-cell neoplasm involving the bone marrow, usually lymphoplasmacytic lymphoma (LPL), is associated with immunoglobulin M paraprotein in the serum. Extramedullary involvement occurs in a subset of patients and is infrequently examined histologically. The files of M.D. Anderson Cancer Center were searched for patients with WM who underwent biopsy of one or more extramedullary sites during the course of disease. Each biopsy specimen was classified using the criteria of the World Health Organization classification. The study group consisted of 44 patients (26 men and 18 women), with a total of 51 specimens obtained from lymph nodes (n = 36), soft tissue (n = 4), spleen (n = 3), skin (n = 2), lung (n = 2), tonsils (n = 1), colon (n = 1), liver (n = 1), and gallbladder (n = 1). Lymphoplasmacytic lymphoma was the most common histologic type, in 40 (78%) samples. This category was morphologically heterogeneous and was further subclassified as lymphoplasmacytic (n = 21), lymphoplasmacytoid (n = 18), and polymorphous (n = 1). Four of these LPL cases morphologically resembled marginal zone B-cell lymphoma. Four additional samples were involved by diffuse large B-cell lymphoma, probably transformed from LPL. Three more samples were involved by LPL with unusual features: two were CD5-positive and one was a composite tumor with classical Hodgkin's disease. Other categories of lymphoma in this group of patients with WM included small lymphocytic lymphoma/chronic lymphocytic leukemia (n = 2), mantle cell lymphoma (n = 1), and follicular lymphoma (n = 1). Waldenstrom macroglobulinemia is most commonly associated with LPL but can rarely occur with other types of B-cell lymphoma. Lymphoplasmacytic lymphoma in patients with WM is morphologically heterogeneous and can be indistinguishable from marginal zone B-cell lymphoma. CD5+ B-cell lymphomas with features otherwise typical of LPL are rare, and we think these tumors are part of the spectrum of LPL.

Adult↗
PubMed2003

Statins increase thrombomodulin expression and function in human endothelial cells by a nitric oxide-dependent mechanism and counteract tumor necrosis factor alpha-induced thrombomodulin downregulation.

Expression of functionally active thrombomodulin (TM) on the luminal surface of endothelial cells is critical for vascular thromboresistance. TM maintains thrombohemorrhagic homeostasis by forming a complex with thrombin, which subsequently loses its procoagulant properties and instead activates protein C. Acquired deficiency of endothelial TM is of particular pathophysiological significance in sepsis and related disorders. We show here that two different 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins), atorvastatin and simvastatin, strongly increase the expression and functional activity of TM in human umbilical vein endothelial cells, human coronary artery endothelial cells, and EA.hy926 endothelial cells. The increase in endothelial TM conferred by statin was prevented by the addition of mevalonic acid, geranylgeranyl-pyrophosphate, and nitric oxide scavenger, and was mimicked by the addition of a specific inhibitor of geranylgeranyl transferase, as well as by nitric oxide donors. Moreover, statin counteracted tumor necrosis factor alpha-induced downregulation of endothelial cell TM. The increase in endothelial cell TM activity in response to statin constitutes a novel pleiotropic (non-lipid-related) effect of these commonly used compounds, and may be of clinical significance in disorders where deficient endothelial TM and protein C activation play a pathophysiological role.

Anticholesteremic Agents↗